Horizontal shaft fuel tank cap with charcoal canister

ABSTRACT

The horizontal shaft fuel tank cap with charcoal canister includes a fuel tank inner cap and fuel tank outer cap. A hollow room with an upper opening is disposed in the center of the fuel tank inner cap. The fuel tank outer cap is disposed above the fuel tank inner cap. The ventilating pipe is disposed in the hollow room and divides the hollow room into filling room and containing room. The first air outlet leading the fuel vapor to the containing room is disposed on the bottom of the containing room. The second air outlets are disposed in the center of the ventilating pipe. The fuel-absorption substrate is disposed in the filling room. The residuary fuel is drained into the fuel tank under negative pressure of the fuel tank. The filtering performance of charcoal powder can be enhanced since it is exempted from long-time fuel soaking.

RELATED U.S. APPLICATIONS

Not applicable.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable.

REFERENCE TO MICROFICHE APPENDIX

Not applicable.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a kind of horizontal shaft fuel tank cap with charcoal canister.

2. Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 37 CFR 1.98.

In the current market, most fuel tank cap contains a containing room filled by charcoal powder. When the inner pressure of the fuel tank is higher than the outer pressure, to achieve internal-external pressure balance, the fuel vapor in the fuel tank passes through and get filtered by charcoal powder, then be discharged to the atmosphere, to achieve the goal of emission control, and less environment pollution. However not all fuel vapor can be absorbed by this way. When the inner temperature is too high, or there is too much vibration within the fuel tank, some liquid fuel enters the containing room, soaks the charcoal powder for long time, and then determines the filtering performance of the charcoal powder.

SUMMARY OF THE INVENTION

The present invention is to solve the current technology problem by providing a kind of horizontal shaft fuel tank with charcoal canister.

The invention solves the above technology problem by the technical solution as follows: a kind of horizontal shaft fuel tank with charcoal canister comprises fuel tank inner cap and fuel tank outer cap. The hollow room with an upper opening is disposed in the center of the said fuel inner cap. The said fuel tank outer cap covering the upper opening of the hollow room is disposed above the said fuel tank inner cap. The ventilating pipe is disposed in the said hollow room and divides the said hollow room into filling room and containing room. The said filling room is disposed above the said containing room. The first air outlet leading the fuel vapor to the said containing room is disposed on the bottom of the said containing room. The second air outlet leading fuel vapor from the said containing room to the said filling room is disposed in the center of the said ventilating pipe. The fuel-absorption substrate is disposed in the said filling room.

The present invention has the advantages that: when gasoline engine stops, the residuary fuel in the containing room and filling room, through the first air outlet on the bottom of the containing room, is drained completely and quickly into the fuel tank under the negative pressure of the fuel tank, for better charcoal powder filtering performance, and less environment pollution.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a structural schematic view of the present invention.

FIG. 2 is the structural schematic view of the present invention with fuel-absorption substrate.

DETAILED DESCRIPTION OF THE DRAWINGS

The following descriptions of the embodiment and its accompanying figures of the present invention are intended to illustrate and not to limit this invention.

FIG. 1 and FIG. 2 show the horizontal shaft fuel tank cap with charcoal canister, comprising fuel tank inner cap 1, and the fuel tank outer cap 2. The hollow room 3 with an upper opening is disposed in the center of fuel tank inner cap 1.

The fuel tank outer cap 2 covering the upper opening of the hollow room 3 is disposed above and non-hermetically connected with the fuel tank inner cap 1, thus the filtered fuel vapor can be discharged easily. The inter wall of fuel tank outer cap 2 and the upper end of the fuel tank inner cap 1 are clamping connected.

The ventilating pipe 4, whose bottom end is contacting with the bottom of the hollow room 3, upper end is contacting with the bottom of the fuel tank outer cap 2, is disposed in the hollow room 3. The ventilating pipe 4 divides the hollow room 3 into the filling room 31 and the containing room 32, and the filling room 31 is disposed above the containing room 32. The bottom end of the ventilating pipe 4 is inverted into the containing room 32. It is preferred that the outer wall of the ventilating pipe 4 and the inter wall of the containing room 32 are hermetically sealed.

Furthermore: the groove 42 connecting with the containing room 32 is disposed in the upper center of the ventilating pipe 4. By this way the weight of the ventilating pipe 4 is reduced and volume of the containing room 32 is increased.

The fuel-absorption substrate 5 is disposed in the filling room 31. The fuel vapor is filtered by the fuel-absorption substrate 5 in the filling room 31, and then discharged to the atmosphere, to achieve the goal of controlling emission, and reducing pollution. Preferred: the fuel-absorption substrate 5 is activated charcoal.

The first air outlet 11 is disposed on the bottom of the containing room 32. The air outlet 11 leads the vapored fuel to the containing room 32, and ensures that the residuary fuel in the containing room 32 is drained completely and quickly into the fuel tank under the negative pressure of the fuel tank, for better absorption of the activated charcoal, and less environmental pollution.

The second air outlets 41 are disposed in the center of the ventilating pipe 4. A plurality of second air outlets 41 leads the fuel vapor from the containing room 32 into the filling room 31.

The first breathing board 6, with the fuel-absorption substrate 5 above, covering the second air outlets 41, is disposed above the bottom of the filling room 31. The first breathing board 6 of two-layer non-woven cloth functions to double filter the fuel vapor entering the filling room 31 from the containing room 32, and prevent the entering of charcoal powder in the filling room 31 to the fuel tank to block carburetor.

The embodiment also includes the second breathing board 9, covering the fuel-absorption substrate 5, which is preferred as two-layer non-woven cloth and disposed above the upper end of the filling room 31, to prevent the leakage of the fuel-absorption substrate 5.

Preferably: the platform supporting the second breathing board 9 is disposed around the upper end of the filling room 31, and the protrusion or reinforce rib is disposed on the bottom of the fuel tank outer cap 2 to push the second breathing board 9 downwards, and the boss supporting the second breathing board 9 is disposed on the ventilating pipe 4.

The upper end of the ventilating pipe 4 can either intersect or not the second breathing board 9. In this embodiment the ventilating pipe 4 intersects the second breathing board 9 until it reaches and contacting with the bottom of the fuel outer cap 2. The ventilating pipe 4 supports not only the second breathing board 9, but also the fuel tank outer cap 2.

The slot 12 with the O-ring 8 inside, is disposed on the bottom of the fuel tank inner cap 1, to connect with the fuel tank, thus reducing environmental pollution caused by the liquid fuel/fuel vapor non-filtered by the fuel-absorption substrate 5 in the filling room 3.

The separating pad 100 is disposed between the fuel tank outer cap 2 and second breathing board 9, pushing the second breathing board 9 downwards to prevent the leakage of fuel-absorption substrate 5.

The embodiment also includes the stainless steel pad 110 which is connected with the bottom of the containing room 32 by the stainless steel rivet 120. The stainless steel rivet 120 intersects the bottom of the containing room 32, and its upper end is in the containing room 32. The stainless steel rivet 32 functions to not only connect the containing room 32, but also drain the deposited liquid fuel in the containing room 32.

The embodiment also includes the spring pad 130, which is disposed under the fuel tank inner cap 1.

The embodiment also includes the anti-drop chain 7 which is disposed and connected with the bottom of the fuel tank inner cap 1.

In the embodiment the ventilation pipe 4 is designed as: the ventilation pipe 4 includes the big supporting column and the small supporting column. The small supporting column is disposed above the big supporting column. The big supporting column is disposed in the containing room 32, and the small supporting column is disposed in the filling room 31. A plurality of second air outlets 41 are disposed on the upper end of the big supporting column, and the upper end of the big supporting column is at the same level with the bottom of the containing room 31. The groove 42 is disposed within the small supporting column.

The little liquid fuel and fuel vapor arising from the fuel tank during working process, following the flow of liquid fuel/fuel vapor, through the first air outlet 11, containing room 32, the second air outlets 41, the first breathing board 6, the filling room 31, and the fuel-absorption substrate 5, get filtered and discharged to the atmosphere through the second breathing board 9 and the small pore on the separating pad 100.

Little liquid fuel is stored in the containing room 32 during the working process. When the gasoline engine stops, following the flow of liquid fuel/fuel vapor, the little residuary fuel in the containing room 32 is drained completely and quickly into the fuel tank under the negative pressure of the fuel tank, for better absorption function of the activated charcoal, and less environment pollution.

When positive pressure or negative pressure occur in the fuel tank, the experimental data about the flow of the liquid fuel entering into the containing room 32 and little liquid fuel drained from the containing room 32 to the fuel tank in every minute is as the following:

Positive/Negative Pressure & Flow Record of the Horizontal Shaft Fuel Tank Cap with Charcoal Canister Positive/Negative Pressure Unit: Kpa, Flow Unit: L/Min Positive Pressure 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 Flow 0.07 1.67 2.75 3.39 3.82 4.19 4.72 5.16 5.40 5.81 Negative Pressure −2.0 −2.5 −3.0 −3.5 −4.0 −4.5 −5.0 −5.5 −6.0 −6.5 Flow 2.47 2.86 3.13 3.43 3.72 4.04 4.20 4.68 4.75 4.96 Note: Vertical and horizontal shaft refer to the installation of the engine.

The above-described preferred embodiment of the present invention is not intended to limit the present invention, any modification within the spirit and principles of the present invention, made by the equivalent replacement, improvement, etc., should be included in the protection of the present invention within the range. 

1. A horizontal shaft fuel tank cap with charcoal canister, comprising: a fuel tank inner cap; a fuel tank outer cap, wherein a hollow room with an upper opening is disposed in a center of said fuel tank inner cap, said fuel tank outer cap covering said upper opening and being disposed above said fuel tank inner cap; a ventilating pipe being disposed in said hollow room and having a bottom end contacting with a bottom of said hollow room, and an upper end contacting with a bottom of said fuel tank outer cap, said ventilating pipe dividing said hollow room into a filling room and a containing room, said filling room being disposed above said containing room; a first air outlet leading fuel vapor to said containing room and being disposed on said bottom of said containing room; and second air outlets leading fuel vapor from said containing room to said filling room being disposed in a center of said ventilating pipe, said filling room containing a fuel-absorption substrate.
 2. The horizontal shaft fuel tank cap with charcoal canister, according to claim 1, further comprising: a first breathing board, with said fuel-absorption substrate above, covering said second air outlets and being disposed above the bottom of said filling room.
 3. The horizontal shaft fuel tank cap with charcoal canister, according to claim 1, further comprising: a second breathing board, covering the said fuel-absorption substrates and being disposed above said upper outlet of said filling room.
 4. The horizontal shaft fuel tank cap with charcoal canister, according to claim 3, the further comprising: a platform supporting said second breathing board and being disposed around said upper end of said filling room, a protrusion being disposed on the bottom of said fuel tank outer cap, pushing said second breathing board downwards, and a boss supporting said second breathing board being disposed on said ventilating pipe.
 5. The horizontal shaft fuel tank cap with charcoal canister claim 3, further comprising: a separating pad, disposed between said fuel tank outer cap and said second breathing board.
 6. The horizontal shaft fuel tank cap with charcoal canister claim 1, wherein said inner wall of said fuel tank outer cap and the upper end of said fuel tank inner cap are clamping connected.
 7. The horizontal shaft fuel tank cap with charcoal canister claim 1, further comprising: a groove connecting with said containing room and being disposed in an upper center of said ventilating pipe.
 8. The horizontal shaft fuel tank cap with charcoal canister claim 1, further comprising: a slot with an O-ring inside said slot, said slot being disposed on the bottom of said fuel tank inner cap and connecting with fuel tank.
 9. The horizontal shaft fuel tank cap with charcoal canister, according to claim 1, further comprising: a stainless steel pad connected with the bottom of said containing room by a stainless steel rivet.
 10. The horizontal shaft fuel tank cap with charcoal canister claim 1, further comprising: an anti-drop chain disposed and connected with the bottom of said fuel tank inner cap. 